stone



UNITED STATES PATENT OFFICE.

B. L. STONE, OF NEW YORK, N. Y.

BURGLAR-ALARM.

Specification forming part of Letters Patent No. 51,489, dated December12, 1865.

To all whom it may concern:

Be it known that I, B. L. STONE, of the city, county, and State of NewYork, have invented a new and Improxed Travelers Burglar- Alarm; and Ido hereby declare that the following is a full, clear, and exactdescription thereof, which will enable those skilled in the art to makeand use the same, reference being had to the accompanying drawings,forming part of this specification, in which- Figure 1 represents theburglar-alarm before it has been set. Fig. 2 is a view of the same whenset. Fig. 3 is a view of the means I adopt for fastening the same to anyarticle in the sleepers room. Fig. 4 is a detached view of a portion ofthe locking arrangement.

Similar letters of reference indicate corresponding parts.

My invention consists in arranging a spring or flexible piece of wire insuch relation to the escapement ot the clock-work in a burglaralarm thatwhen the cord which connects the said flexible rod to the door or windowis slackened or set free the escapement will have free play to operateupon the bell, but when said end is held tight the whole apparatus willremain in a perfectly quiescent state.

It also consists in a locking arrangement for holding the said flexiblerod so as to prevent the escapement from operating until the alarm hasbeen adjusted or set for use, when the locking-arm can be withdrawn,leaving the said flexible rod free to act so soon as the cord isslackened.

It also consists in a peculiar manner of connecting the cord with thesaid flexible rod.

It also consists in anew device I employ for attaching the cord to thedoor or window, the said device consisting of two flat springs divergingfrom each other at the ends while the other ends are connected togetherby a plate having a suitable nose or projection for the door or windowto strike against to throw it out of place.

It also consists in combining with the device an ordinary or anysuitable clasp for fastening it to a bed-post or in any desirable place.

To enable others to understand my invention, I will proceed to describeit.

A represents the case or box for containing the apparatus.

B is the clock-work, consisting of such parts only as are necessary tooperate a bell-hammer, a, for the purpose of striking the alarmbell.

O is the flexible rod or spring, which is attached to the pallet b ofthe escapement c in such manner that when the said rod is drawn towardthe clock-work the pallet will be caused to hold the escapement-wheel,and therefore prevent any action thereof; but when it is allowed tospring backward or in an opposite direction the pallet will release theescapeinent, and thus cause the bell-ham mer a,whose crank or arm isattached to the shaft of the pallet to operate freely and cause the saidhammer to play upon the bell. The upper end of this flexible rod has aneye, at, in it, through which is run a wire, 0, which is attached to ashaft, f, having its hearings in plates D suitably arranged above theclock-work. This shaft carries an arm, g, to which is attached anotherwire, it, extending to the outside of the case, where the string 1' isattached to it. This intermediate connecting apparatus I find operatesbetter than were the wire it connected directly to the flexible rod 0;though I propose sometimes adopting this latter course, when simplicityof construction is desired.

Ej k l m is the apparatus for locking the rod 0 after the clock-work hasbeen wound up, consisting of a thumb-screw, E,on the outside of thecase, to which is attached a rod, j, having fastened to it an arm, k,with a forked end which presses against the flexible rod (J and pressesit in toward the clock-work, and thus prevents the pallet allowing theescapementwheel to operate, as shown clearly in Fig. 1.

l is a spring, arranged so as to throw the arm 7G forward against theflexible rod 0, so soon as the rod j is allowed to fly inward, bybringing its shoulder over a hole into which it sinks, as will be seenby reference to Figs. 1 and 2, this peculiar arran gementbein g shown indetail in Fig. 4. This locking arrangement is used after the clock-workhas been. wound up and the device is being set for use, as shown inFig. 1. In Fig.2, where the alarm is shown as set, the lockingarrangement is thrown out of operation, as will be seen by reference tothat figure.

a is the cord, having on it a device, F, for tightening or loosening itas the distance the alarm is placed from the door or window may require.

G is the device to insert in the crack of the door or window. To insertit, its two springs 0 0 are pressed together, and in this way forcedinto the cracks of the door or window, where it will remain withoutliability of displacement until the door or Window is opened, which willstrike against a nose,p, and throw the said device out of the crack, andthus release the flexible rod 0, which puts the whole alarm inoperation.

H is a clamp, which is hinged to the back or side of the ease, having ascrew, g, for tightening its hold upon any article in the usual manner.The hinge 4 enables the clamp to fall back against the case A, and thusbe out of the way.

This alarm will be found perfect in its operation, easily applied, andof a very convenient size for oarryingin fact so small that it may becarried in the pocket without much, if any, embarrassment.

I do not confine myself to the precise arran gement as herein specified.

What I claim as new, and desire to secure by Letters Patent, is-- 1.Constructing the clamp H with a hingejoint to enable it to be folded upclose against the back or side of the case, substantially as specified.

2. The device E j is hit, or its equivalent, for holding the rod fromoperating after the clockwork has been wound up and while the alarm isbeing set.

3. The shaft f, connected to the rods 0 and h, arranged substantially inthe manner and for the purposes herein mentioned.

The above specification of my lllVGlltlOll signed by me this 10th day ofApril, 1865.

B. L. STONE.

Witnesses M. M. LIVINGSTON, O. L. TOPLIFF.

